And police believe one of those men was the father of the unborn baby.

Isiaha Devon Milligan, 24, of Johnson City; Avios Griffin, 24, of Johnson City; Monte Brewer Jr., 27, of Cleveland, Tennessee; and Eugene Glover, 31, of Chattanooga, were charged with first-degree murder and first-degree murder in commission of a felony, according to a Johnson City Police Department press release.

Milligan was also charged with two counts of solicitation of first-degree murder.

After a 10-month investigation, Johnson City police presented their findings to a Washington County grand jury on May 4, after which all four men were indicted on charges related to the shooting death of Rebekah Thompson, who also went by Stacy McGee.

Police said the four men were arrested during a two-day operation in Johnson City and Chattanooga.

Thompson’s infant daughter was also sitting in the car, but she was not injured, police said. Immediately following her mother’s death, a caseworker with the Department of Children’s Services took custody of the baby until further decisions could be made.

A search warrant filed in the case described what led Johnson City police investigators to believe Milligan was involved in the slaying.

Filed July 25, the day after Thompson’s death, by Investigator Matthew Gryder, the warrant sought Washington County Criminal Court Judge Lisa Rice’s permission to search cellphones owned by Milligan and confiscated by police.

Gryder stated in the warrant affidavit that Milligan and Thompson were former lovers and Thompson had told others that Milligan was the father of her unborn child.

Investigators also received screen shots of messages, believed to be from a Facebook mobile application, Thompson had forward to a friend, according to the search warrant.

“The messages concerned Thompson telling Milligan that she was pregnant with his child,” Gryder wrote. “Milligan denied that he was the father of the child and told her he would wait on a DNA test to confirm that he was the father of the child. Additionally, Milligan’s nickname, 50, was listed in the contact list of Thompson’s phone.”

When police interviewed Milligan, he allowed them to search his residence, and police found two cellphones belonging to Milligan, according to the warrant.

“Affiant (Gryder) believes there are communications with Thompson on the described telephones. These communications may be evidence related to Thompson’s murder,” the warrant states.

The warrant allowed police to search the two phones for call logs; contacts; text messages; multimedia messages; messages sent or received through applications, online services and social media platforms; photographs; videos; internet search histories; location data and location searches; and user accounts for apps and social media.

Witnesses initially told police they had seen someone, described as a black man wearing a red and black hoodie, hanging around the area where Thompson was parked about 15 minutes before the shooting.

The witnesses said the man left, but returned in a dark-colored vehicle, possibly a Ford Focus, with tinted windows. The man reportedly got out on the driver’s side, went directly to Thompson’s car, fired the gun through the opened window and left in the same car in which he had arrived.

Police said they believed Thompson grew up in Mississippi and was adopted at some point in her life and given the name Rebekah Thompson. Neighbors near her Keystone community apartment said Thompson had only lived in the apartment at 404 S. Broadway St. a few months before her death.

“From witness statements, the subject walked straight to her window, pulled the gun and shot her once and then got out of there, so at this point in time we do believe she was targeted,” he said.

The FBI, the Tennessee Bureau of Investigation, the U.S. Attorney General’s Office, the First Judicial District Attorney General’s Office, the Chattanooga Police Department and the Hamilton County Sheriff’s Department all assisted in the investigation.

All four men were being held on $500,000 bond at the Washington County Detention Center.

WRCBtv in Chattanooga reported in August 2014 that Griffin and two other men were arrested on weapons charges related to a complaint that three men pointed a gun at a security guard at the Country Hearth Inn and Suites. Griffin, who was reportedly driving, was charged with unlawful possession of a weapon, theft of property, possession of a firearm while driving intoxicated, driving on a revoked license and underage drinking.

Police said the investigation remains ongoing and declined to provide further statements about the case regarding motive or evidence collected.

“It is our hope that these arrests will bring some comfort to Ms. Thompson’s (McGee) family as well as relief to the citizens of Johnson City that the perpetrators of this horrific act have been arrested,” the Johnson City Police Department statement said.